44 research outputs found
Biodiversity of Indigenous Saccharomyces Populations from Old Wineries of South-Eastern Sicily (Italy): Preservation and Economic Potential
In recent years, the preservation of biodiversity has become an important issue. Despite much public discussion, however, current practices in the food industry seldom take account of its potential economic importance: on the contrary, the introduction of industrialized agriculture practices over large areas has often resulted in a dramatic reduction in biodiversity
Search for dark matter produced in association with bottom or top quarks in √s = 13 TeV pp collisions with the ATLAS detector
A search for weakly interacting massive particle dark matter produced in association with bottom or top quarks is presented. Final states containing third-generation quarks and miss- ing transverse momentum are considered. The analysis uses 36.1 fb−1 of proton–proton collision data recorded by the ATLAS experiment at √s = 13 TeV in 2015 and 2016. No significant excess of events above the estimated backgrounds is observed. The results are in- terpreted in the framework of simplified models of spin-0 dark-matter mediators. For colour- neutral spin-0 mediators produced in association with top quarks and decaying into a pair of dark-matter particles, mediator masses below 50 GeV are excluded assuming a dark-matter candidate mass of 1 GeV and unitary couplings. For scalar and pseudoscalar mediators produced in association with bottom quarks, the search sets limits on the production cross- section of 300 times the predicted rate for mediators with masses between 10 and 50 GeV and assuming a dark-matter mass of 1 GeV and unitary coupling. Constraints on colour- charged scalar simplified models are also presented. Assuming a dark-matter particle mass of 35 GeV, mediator particles with mass below 1.1 TeV are excluded for couplings yielding a dark-matter relic density consistent with measurements
Identification of genetic variants associated with Huntington's disease progression: a genome-wide association study
Background Huntington's disease is caused by a CAG repeat expansion in the huntingtin gene, HTT. Age at onset has been used as a quantitative phenotype in genetic analysis looking for Huntington's disease modifiers, but is hard to define and not always available. Therefore, we aimed to generate a novel measure of disease progression and to identify genetic markers associated with this progression measure. Methods We generated a progression score on the basis of principal component analysis of prospectively acquired longitudinal changes in motor, cognitive, and imaging measures in the 218 indivduals in the TRACK-HD cohort of Huntington's disease gene mutation carriers (data collected 2008–11). We generated a parallel progression score using data from 1773 previously genotyped participants from the European Huntington's Disease Network REGISTRY study of Huntington's disease mutation carriers (data collected 2003–13). We did a genome-wide association analyses in terms of progression for 216 TRACK-HD participants and 1773 REGISTRY participants, then a meta-analysis of these results was undertaken. Findings Longitudinal motor, cognitive, and imaging scores were correlated with each other in TRACK-HD participants, justifying use of a single, cross-domain measure of disease progression in both studies. The TRACK-HD and REGISTRY progression measures were correlated with each other (r=0·674), and with age at onset (TRACK-HD, r=0·315; REGISTRY, r=0·234). The meta-analysis of progression in TRACK-HD and REGISTRY gave a genome-wide significant signal (p=1·12 × 10−10) on chromosome 5 spanning three genes: MSH3, DHFR, and MTRNR2L2. The genes in this locus were associated with progression in TRACK-HD (MSH3 p=2·94 × 10−8 DHFR p=8·37 × 10−7 MTRNR2L2 p=2·15 × 10−9) and to a lesser extent in REGISTRY (MSH3 p=9·36 × 10−4 DHFR p=8·45 × 10−4 MTRNR2L2 p=1·20 × 10−3). The lead single nucleotide polymorphism (SNP) in TRACK-HD (rs557874766) was genome-wide significant in the meta-analysis (p=1·58 × 10−8), and encodes an aminoacid change (Pro67Ala) in MSH3. In TRACK-HD, each copy of the minor allele at this SNP was associated with a 0·4 units per year (95% CI 0·16–0·66) reduction in the rate of change of the Unified Huntington's Disease Rating Scale (UHDRS) Total Motor Score, and a reduction of 0·12 units per year (95% CI 0·06–0·18) in the rate of change of UHDRS Total Functional Capacity score. These associations remained significant after adjusting for age of onset. Interpretation The multidomain progression measure in TRACK-HD was associated with a functional variant that was genome-wide significant in our meta-analysis. The association in only 216 participants implies that the progression measure is a sensitive reflection of disease burden, that the effect size at this locus is large, or both. Knockout of Msh3 reduces somatic expansion in Huntington's disease mouse models, suggesting this mechanism as an area for future therapeutic investigation
Rilevamento ed enumerazione di Legionella spp. in matrici ambientali: confronto tra il metodo colturale di riferimento e un metodo basato sull'impiego di sonde molecolari fluorescenti genere- e specie-specifiche.
Le legionellosi sono infezioni occasionalmente acquisite dall’uomo in seguito all’esposizione a una fonte ambientale contaminata dai batteri Legionella (per esempio l’acqua). Un rilevamento rapido e accurato di Legionella nell’ambiente consente di ridurre notevolmente il rischio di contrarre l’infezione. Il metodo colturale è considerato il “gold standard” nell’indagine ambientale per Legionella ma recentemente il metodo ScanVIT-LegionellaTM (Vermicon) è stato proposto come uno strumento diagnostico in grado di coniugare rapidità ed efficacia. Nella ricerca descritta in questa tesi abbiamo testato il metodo ScanVIT-Legionella in campioni di acqua e abbiamo confrontato i valori di rilevamento di Legionella spp. ottenuti ricorrendo a due diverse procedure di “decontaminazione” dei campioni ambientali: trattamento con il calore e con acidi. Abbiamo raccolto un totale di 19 campioni di acqua provenienti dall’impianto idrico dell’ospedale universitario di Siena (Italia). Abbiamo analizzato ciascun campione con il metodo ScanVIT-Legionella associato sia a decontaminazione con il calore che con acidi mentre il metodo colturale associato al trattamento con il calore è stato impiegato come metodo di riferimento. Gli effetti di entrambe le procedure di decontaminazione e delle diverse metodiche diagnostiche sono stati valutati paragonando il numero di campioni positivi e negativi a Legionella e i valori di concentrazione (UFC/L) di Legionella misurati per ciascun campione. Il metodo ScanVIT ha mostrato un’elevata sensibilità nel rilevare Legionella spp. nei campioni d’acqua con entrambi i trattamenti di decontaminazione considerati. Inoltre, questo metodo ha rilevato concentrazioni di Legionella maggiori di quelle rilevate dal metodo di riferimento. Il trattamento con acidi si è rivelato invece quale scelta migliore per rilevare specie L. non-pneumophila con il metodo ScanVIT, sia in termini di sensibilità che di resa batterica.
Legionellosis are human, occasionally-acquired infections due to the exposure to an environmental source contaminated by Legionella bacteria (water, e.g.). A quick and accurate detection of Legionella in the environment allows a significant reduction of the infection risk. The culture method is considered the “gold standard” for the environmental investigation of Legionella but the ScanVIT-Legionella assay has been recently proposed as a rapid and effective diagnostic tool. In this work, we tested the ScanVIT-Legionella assay and compared the results of two different decontamination procedures (i.e. the heating and the acid-treatment) on the detection of Legionella spp.. We collected 19 water samples from the teaching hospital in Siena (Italy). We analyzed each sample by ScanVIT in association to either acid or heat treatment, while the culture method with heat treatment was used as standard. The effects of both decontamination procedures and the different detection methods were evaluated comparing the number of Legionella-positive and -negative samples and the recovery rates (CFU/L) of Legionella. We find that ScanVIT method with both decontamination treatments is highly sensitive in detecting L. pneumophila in water and it yields a higher recovery compared to the standard method. At variance, the acid-treatment represents the best choice to detect L. non-pneumophila by ScanVIT in terms of both sensitivity and recovery
Increasing voltage gradient electrophoresis of DNA
We developed a method which allows electrophoretic fractionation of DNA in an agarose matrix according to an increasing current gradient, using a previously designed [R. Barbieri, V. Izzo, M.A. Costa, G. Giudice, G. Duro, Anal. Biochem. 212 (1993) 168; M.R. Asaro, V. Izzo, R. Barbieri, J. Chromatogr. A 855 (1999) 723] voltage gradient apparatus. This method allows the separation of different DNA fragments by increasing the distances of the components fractionated in the gel, revealing small differences in the length of different DNA components
A study on hot-beverages vending machines: what do we daily drink?
Background
Hot-drinks vending machines are disseminated worldwide and
millions of drinks are served every day. Because of a lack of
studies on hot-drinks related illnesses, the aim of the study is
to identify the presence and load of bacterial species,
potentially harmful for consumers, within hot-drinks vending
machines.
Methods
This preliminary cross sectional study was carried out in April
2015 at the University of Siena, Italy. 12 samples from 4 hotdrinks
vending machines(VM) were taken using a sterile swab;
samples were taken from: i) Dispense Area, ii) Nozzle, iii) Glass-
Holder. The samples were analyzed in the laboratory and sown
on selective terrains. Results were expressed both in terms of
average CFU/swab between the samples of the 4 VM, and in
terms of CFU/cm2, relying on guidelines of surfaces sanitation,
which fix the limit in 50 CFU/cm2. Total Microbial Load(TML)
at 36C and 22C was assessed for mesophilic and psychrophilic
contamination. Descriptive analysis were performed.
Results
All the analyzed surfaces exceeded the fixed limit. Nozzles were
the mostly contaminated, showing a bacterial load of 82500
CFU/swab (SD:41662), correspondent to 2063 CFU/cm2.
Dispense Area showed an high presence of bacteria (TML
from 28125 CFU/swab to Uncountable Microbial Colonies
(UMC) both at 36C, and at 22C). The TML of the Glass-
Holder went from 1380 CFU/swab to UMC at 36C, and from
1050 CFU/swab to UMC at 22C. In particular the nozzle
showed a mean of 22770 CFU/swab(SD:27444), correspondent
to 569 CFU/cm2 of Staphylococcus spp, and 25399 CFU/swab
(SD:35252), correspondent to 635 CFU/cm2 of Enterococcus
spp.
Conclusions
Given the high number of CFU/swab and the presence of
harmful species that we identified so far, VM may constitute a
potential threat for consumer, reason for which further studies
are recommendable.
Key messages
The use of hot beverage vending machines is increasing in
the world because of changes in food habits
Hot beverage vending machines may constitute a potential
threat because of high microbial contaminants, including
pathogen ones, which we have identifie
Correction: Biodiversity of Indigenous Saccharomyces Populations from Old Wineries of South-Eastern Sicily (Italy): Preservation and Economic Potential
Mt-DNA RFLP patterns of 14 isolates (indicated) used for the 100 liter fermentations of 2004.
<p>A. Patterns obtained with the <i>RsaI</i> enzyme. B. patterns obtained with the <i>HinfI</i> enzyme. M, molecular marker (1 kb ladder, BHD).</p
Mt-DNA RFLP patterns obtained at the end of fermentation from Nero d'Avola (lane 3) and Frappato (lane 4), inoculated with B2–48 (A), B2–25 (B), ICV-D254 (C) and QD-145 (D).
<p>Control RFLP patterns obtained with DNA from the pure cultures of each isolate are shown in lane 2 of each panel. Lane 1, molecular marker (1 kb ladder, BDH).</p